To get to 40m/s from zero and slow down to zero again before you get to 17meters you will need 9g acceleration. Perhaps you could use pneumatics to get that kind of power on your crane. Another extreme option is a collision to get your object to where it needs to be, kind of like when you play billiards. you would need to calculate where the object needs to go and punch it there.

One problem you're going to face is that the system itself (17 meters long) will be heavier than the object you move. Thus, you have to specify the system for the weight/inertia of the gantry, rather than the object itself.

How much precision do you need? Decimeters? Centimeters? Millimeters? Microns?

Sounds like you need an XY gantry and a Z pulley. I'm assuming it's OK to enclose the are with the gantry supports.We're probably talking chains or heavy timing belts; kilowatts of electric motor power. Maybe linear drives instead, although that might cost a lot and be hard to get in sufficient speeds.What's your budget?

The hoist seems like a problem, though, because it will move like a pendulum when the gantry is moving. Maybe some advanced math will let you tune the deceleration of the gantry to the length of the pendulum and make it end up in the place you want it with zero movement. Maybe.

Here is an idea: Instead of having one arm, use a two dimensional array of arms suspended from the ceiling. You could use pneumatic tubes to push the arms down. The arms could be spaced close together and can be lowered very quickly ( gravity assisted ). When a target and destination is selected have the arms that are in line with the path come down. The first arm will grab the target and pass it to the next arm, until it gets to the final arm. Once the first arm grabs the target object each arm can have a predetermined motion to pass the object to its neighbour very quickly.

If you want to get fancy you could even lower a container for you target object. The first arm would encase the object in the container and than it could use a magnetic force between the arms to slide the container to its destination. In effect each arm would act as a magnetic rail tile.